crypto: add support for the cast5-128 cipher algorithm

A new cipher algorithm 'cast-5-128' is defined for the
Cast-5 algorithm with 128 bit key size. Smaller key sizes
are supported by Cast-5, but nothing in QEMU should use
them, so only 128 bit keys are permitted.

The nettle and gcrypt cipher backends are updated to
support the new cipher and a test vector added to the
cipher test suite. The new algorithm is enabled in the
LUKS block encryption driver.

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
This commit is contained in:
Daniel P. Berrange 2016-02-10 17:07:42 +00:00
parent aa41363598
commit 084a85eedd
5 changed files with 58 additions and 2 deletions

View File

@ -29,6 +29,7 @@ bool qcrypto_cipher_supports(QCryptoCipherAlgorithm alg)
case QCRYPTO_CIPHER_ALG_AES_128: case QCRYPTO_CIPHER_ALG_AES_128:
case QCRYPTO_CIPHER_ALG_AES_192: case QCRYPTO_CIPHER_ALG_AES_192:
case QCRYPTO_CIPHER_ALG_AES_256: case QCRYPTO_CIPHER_ALG_AES_256:
case QCRYPTO_CIPHER_ALG_CAST5_128:
return true; return true;
default: default:
return false; return false;
@ -84,6 +85,10 @@ QCryptoCipher *qcrypto_cipher_new(QCryptoCipherAlgorithm alg,
gcryalg = GCRY_CIPHER_AES256; gcryalg = GCRY_CIPHER_AES256;
break; break;
case QCRYPTO_CIPHER_ALG_CAST5_128:
gcryalg = GCRY_CIPHER_CAST5;
break;
default: default:
error_setg(errp, "Unsupported cipher algorithm %d", alg); error_setg(errp, "Unsupported cipher algorithm %d", alg);
return NULL; return NULL;
@ -113,7 +118,18 @@ QCryptoCipher *qcrypto_cipher_new(QCryptoCipherAlgorithm alg,
ctx->blocksize = 8; ctx->blocksize = 8;
} else { } else {
err = gcry_cipher_setkey(ctx->handle, key, nkey); err = gcry_cipher_setkey(ctx->handle, key, nkey);
ctx->blocksize = 16; switch (cipher->alg) {
case QCRYPTO_CIPHER_ALG_AES_128:
case QCRYPTO_CIPHER_ALG_AES_192:
case QCRYPTO_CIPHER_ALG_AES_256:
ctx->blocksize = 16;
break;
case QCRYPTO_CIPHER_ALG_CAST5_128:
ctx->blocksize = 8;
break;
default:
g_assert_not_reached();
}
} }
if (err != 0) { if (err != 0) {
error_setg(errp, "Cannot set key: %s", error_setg(errp, "Cannot set key: %s",

View File

@ -23,6 +23,7 @@
#include <nettle/aes.h> #include <nettle/aes.h>
#include <nettle/des.h> #include <nettle/des.h>
#include <nettle/cbc.h> #include <nettle/cbc.h>
#include <nettle/cast128.h>
#if CONFIG_NETTLE_VERSION_MAJOR < 3 #if CONFIG_NETTLE_VERSION_MAJOR < 3
typedef nettle_crypt_func nettle_cipher_func; typedef nettle_crypt_func nettle_cipher_func;
@ -63,6 +64,18 @@ static void des_decrypt_wrapper(cipher_ctx_t ctx, cipher_length_t length,
des_decrypt(ctx, length, dst, src); des_decrypt(ctx, length, dst, src);
} }
static void cast128_encrypt_wrapper(cipher_ctx_t ctx, cipher_length_t length,
uint8_t *dst, const uint8_t *src)
{
cast128_encrypt(ctx, length, dst, src);
}
static void cast128_decrypt_wrapper(cipher_ctx_t ctx, cipher_length_t length,
uint8_t *dst, const uint8_t *src)
{
cast128_decrypt(ctx, length, dst, src);
}
typedef struct QCryptoCipherNettle QCryptoCipherNettle; typedef struct QCryptoCipherNettle QCryptoCipherNettle;
struct QCryptoCipherNettle { struct QCryptoCipherNettle {
void *ctx_encrypt; void *ctx_encrypt;
@ -80,6 +93,7 @@ bool qcrypto_cipher_supports(QCryptoCipherAlgorithm alg)
case QCRYPTO_CIPHER_ALG_AES_128: case QCRYPTO_CIPHER_ALG_AES_128:
case QCRYPTO_CIPHER_ALG_AES_192: case QCRYPTO_CIPHER_ALG_AES_192:
case QCRYPTO_CIPHER_ALG_AES_256: case QCRYPTO_CIPHER_ALG_AES_256:
case QCRYPTO_CIPHER_ALG_CAST5_128:
return true; return true;
default: default:
return false; return false;
@ -143,6 +157,18 @@ QCryptoCipher *qcrypto_cipher_new(QCryptoCipherAlgorithm alg,
ctx->blocksize = AES_BLOCK_SIZE; ctx->blocksize = AES_BLOCK_SIZE;
break; break;
case QCRYPTO_CIPHER_ALG_CAST5_128:
ctx->ctx_encrypt = g_new0(struct cast128_ctx, 1);
ctx->ctx_decrypt = NULL; /* 1 ctx can do both */
cast5_set_key(ctx->ctx_encrypt, nkey, key);
ctx->alg_encrypt = cast128_encrypt_wrapper;
ctx->alg_decrypt = cast128_decrypt_wrapper;
ctx->blocksize = CAST128_BLOCK_SIZE;
break;
default: default:
error_setg(errp, "Unsupported cipher algorithm %d", alg); error_setg(errp, "Unsupported cipher algorithm %d", alg);
goto error; goto error;

View File

@ -27,6 +27,7 @@ static size_t alg_key_len[QCRYPTO_CIPHER_ALG__MAX] = {
[QCRYPTO_CIPHER_ALG_AES_192] = 24, [QCRYPTO_CIPHER_ALG_AES_192] = 24,
[QCRYPTO_CIPHER_ALG_AES_256] = 32, [QCRYPTO_CIPHER_ALG_AES_256] = 32,
[QCRYPTO_CIPHER_ALG_DES_RFB] = 8, [QCRYPTO_CIPHER_ALG_DES_RFB] = 8,
[QCRYPTO_CIPHER_ALG_CAST5_128] = 16,
}; };
static size_t alg_block_len[QCRYPTO_CIPHER_ALG__MAX] = { static size_t alg_block_len[QCRYPTO_CIPHER_ALG__MAX] = {
@ -34,6 +35,7 @@ static size_t alg_block_len[QCRYPTO_CIPHER_ALG__MAX] = {
[QCRYPTO_CIPHER_ALG_AES_192] = 16, [QCRYPTO_CIPHER_ALG_AES_192] = 16,
[QCRYPTO_CIPHER_ALG_AES_256] = 16, [QCRYPTO_CIPHER_ALG_AES_256] = 16,
[QCRYPTO_CIPHER_ALG_DES_RFB] = 8, [QCRYPTO_CIPHER_ALG_DES_RFB] = 8,
[QCRYPTO_CIPHER_ALG_CAST5_128] = 8,
}; };
static bool mode_need_iv[QCRYPTO_CIPHER_MODE__MAX] = { static bool mode_need_iv[QCRYPTO_CIPHER_MODE__MAX] = {

View File

@ -59,11 +59,14 @@
# @aes-192: AES with 192 bit / 24 byte keys # @aes-192: AES with 192 bit / 24 byte keys
# @aes-256: AES with 256 bit / 32 byte keys # @aes-256: AES with 256 bit / 32 byte keys
# @des-rfb: RFB specific variant of single DES. Do not use except in VNC. # @des-rfb: RFB specific variant of single DES. Do not use except in VNC.
# @cast5-128: Cast5 with 128 bit / 16 byte keys
# Since: 2.6 # Since: 2.6
## ##
{ 'enum': 'QCryptoCipherAlgorithm', { 'enum': 'QCryptoCipherAlgorithm',
'prefix': 'QCRYPTO_CIPHER_ALG', 'prefix': 'QCRYPTO_CIPHER_ALG',
'data': ['aes-128', 'aes-192', 'aes-256', 'des-rfb']} 'data': ['aes-128', 'aes-192', 'aes-256',
'des-rfb',
'cast5-128']}
## ##

View File

@ -165,6 +165,15 @@ static QCryptoCipherTestData test_data[] = {
"ffd29f1bb5596ad94ea2d8e6196b7f09" "ffd29f1bb5596ad94ea2d8e6196b7f09"
"30d8ed0bf2773af36dd82a6280c20926", "30d8ed0bf2773af36dd82a6280c20926",
}, },
{
/* RFC 2144, Appendix B.1 */
.path = "/crypto/cipher/cast5-128",
.alg = QCRYPTO_CIPHER_ALG_CAST5_128,
.mode = QCRYPTO_CIPHER_MODE_ECB,
.key = "0123456712345678234567893456789A",
.plaintext = "0123456789abcdef",
.ciphertext = "238b4fe5847e44b2",
},
}; };